Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758257AbYFTVZk (ORCPT ); Fri, 20 Jun 2008 17:25:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753230AbYFTVZb (ORCPT ); Fri, 20 Jun 2008 17:25:31 -0400 Received: from mx1.redhat.com ([66.187.233.31]:52502 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752849AbYFTVZa (ORCPT ); Fri, 20 Jun 2008 17:25:30 -0400 Date: Fri, 20 Jun 2008 17:25:26 -0400 (EDT) From: Mikulas Patocka To: David Miller cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, agk@redhat.com Subject: Re: stack overflow on Sparc64 In-Reply-To: <20080620.142034.30884440.davem@davemloft.net> Message-ID: References: <20080620.102601.06998427.davem@davemloft.net> <20080620.142034.30884440.davem@davemloft.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1271 Lines: 39 On Fri, 20 Jun 2008, David Miller wrote: > From: Mikulas Patocka > Date: Fri, 20 Jun 2008 17:14:41 -0400 (EDT) > >> Are you sure? What about this: >> ide-io.c:ide_intr >> if (drive->unmask) >> local_irq_enable_in_hardirq(); >> >> or this: >> kernel/irq/handle.c:handle_IRQ_event >> if (!(action->flags & IRQF_DISABLED)) >> local_irq_enable_in_hardirq(); >> >> >> --- how is number of nested interrupts here supposed to be limited? >> >> If these things are not limited, you get at most as many nested handlers >> as there are hardware interrupts, which means crash. > > It means i386 and every other platform potentially has the same exact > problem. > > What point wrt. sparc64 are you trying to make here? :-) The difference is that i386 takes minimum 4 bytes per stack frame and sparc64 192 bytes per stack frame. So this problem will kill sparc64 sooner. But yes, it is general problem and should be solved in arch-independent code. Mikulas -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/